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101.
The scope of our research is the development of polymer-based bioabsorbable stents for urologic applications and in vitro testing of tissue reactions of cultured ureteral and urethral segments induced by implanted polymer stent prototypes. For these purposes a tissue cultivation model was developed using selected techniques of tissue engineering. Essential advantages of degradable over nondegradable urethral stents are elimination of the adverse extraction of epithelialized stents and the potential for recovery of organ-specific functionality. Moreover, the biocompatibility of a degradable urethral stent could potentially reduce the risk of restenosis due to hyperplasia and could be used, even repeatedly, for the treatment of a number of subvesical obstructions. For the treatment of tumor-induced strictures, application of degradable polymer stents coated with cytostatic drugs may be possible. The mechanical effect of the drug-loaded stent as a “place holder” could be complemented by adjuvant or palliative approaches such as local chemotherapy. We have developed and tested in vitro a degradable urethral stent incorporated with the model drug methotrexate for local drug delivery (LDD) by diffusion and during stent degradation.  相似文献   
102.
Heparin-induced thrombocytopenia (HIT) represents a serious side effect caused by an atypical immune response to platelet factor 4 leading to platelet activation and thrombin formation. These patients are at high risk of thromboembolism, with a rapid drop in platelet count between days 5 and 14 after the initiation of heparin treatment. In single cases, especially after major surgery, platelet count reduction might be absent or hidden by preceding thrombocytosis. Different clinical manifestations of HIT include unspecific skin reactions with potential necrosis at the site of heparin injection, mostly after the application of unfractionated heparin but also with low molecular weight heparin. In heparin-induced skin necrosis, administration of unfractionated or low molecular weight heparin is contraindicated and heparin therapy should be stopped immediately. Instead, an alternative anticoagulant in the form of a direct thrombin inhibitor such as argatroban, and respectively lepirudin, or danaparoid sodium must be administered. Due to frequent misinterpretations of heparin-induced unspecific skin reactions, especially in the absence of thrombocytopenia, we present two case reports which should increase the awareness of HIT’s various clinical pictures.  相似文献   
103.
The first part of this serial paper dealt with the medical criteria used in evaluation of the clinical picture caused by physical stress and the evaluation of other candidate causes and was published in issue no. 3/2005 (pp. 711–752) of Trauma and Berufskrankheit. This follow-up paper (II) presents criteria to be used in the evaluation of whether it is necessary to give up the occupations putting the spine at risk and in estimation of the degree of disability.  相似文献   
104.
105.
Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations.  相似文献   
106.

Background  

The telomeric region of mouse chromosome 12 has previously shown frequent allelic loss in murine lymphoma. The Bcl11b gene has been identified and suggested as a candidate tumor suppressor gene within this region. In this study, we aimed to elucidate whether Bcl11b is mutated in lymphomas with allelic loss, and whether the mutations we detected conferred any effect on cell proliferation and apoptosis.  相似文献   
107.
ZusammenfassungEinleitung In unserer Klinik wird seit über 30 Jahren die operative Behandlung von Klumpfüßen über einen dorsomedialen Zugang durchgeführt. Postoperativ erfolgt zunächst eine Gipsbehandlung, dann eine konsequente Nachbehandlung mit Orthesen und Winkeleinlagen.Material und Methode Zwischen dem 1. 6. 1986 und dem 31. 12. 2000 wurden 130 primäre Klumpfußweichteiloperationen bei 86 Patienten durchgeführt. 119 (92%) Füße konnten nach durchschnittlich 4,5 Jahren klinisch-radiologisch nachuntersucht werden. Das durchschnittliche Alter bei der Operation betrug 7,6 Monate. Klassifikation nach Dimeglio und Score nach Laaveg und Ponseti dienten zur Beurteilung. Die gemessenen Winkel in den belasteten Röntgenbildern des Fußes a.p. und seitlich prä- und postoperativ wurden verglichen, Komplikationen und Rezidive dokumentiert.Ergebnisse 29 (22,3%) Füße wiesen einen Schweregrad IV nach Dimeglio, 58 (44,6%) Grad III und 43 (33,1%) Grad II auf. Ein Klumpfußrezidiv war bei 9 (7,6%) Fällen zu beobachten. Alle Winkel verbesserten sich signifikant. Bei der Nachuntersuchung wurden durchschnittlich 95,4±9,2 Punkte nach dem Score von Laaveg und Ponseti erzielt.Schlussfolgerung Der von uns verwendete dorsomediale Zugangsweg erlaubt eine ausgezeichnete Klumpfußkorrektur mit geringer Rezidiv- und Komplikationsrate.  相似文献   
108.
Clonidine (10 micrograms X kg-1) reduced by almost 50% the increase in plasma neuropeptide (NPY)-like immunoreactivity (-LI) induced by preganglionic nerve stimulation at 8 Hz. This effect was reversed by yohimbine (1 mg X kg-1) which caused a three-fold increase of the plasma NPY-LI. Prazosin (1 mg X kg-1) had no such effect. Guanethidine (5 mg X kg-1) reduced the stimulation-evoked increase in plasma NPY-LI. It is concluded that the release of NPY-LI evoked by nerve stimulation from sympathetic nerve terminals is controlled by a presynaptic alpha 2-adrenoceptor-mediated mechanism.  相似文献   
109.
Background and aims The aim of this study was to assess the diagnostic value of image guided percutaneous fine needle aspiration (FNA) biopsy in equivocal mediastinal masses.Patients Sixty-six patients with an equivocal mediastinal mass who underwent FNA biopsy between 1993 and 2003 were eligible for final analysis. The cytological and definitive diagnosis of masses were grouped as primary 22 (33%)−30 (46%) and secondary (metastatic) neoplasms 18 (27%)−18 (27%) and nonneoplastic lesions 20 (30%)−18 (%27) respectively.Results The diagnostic accuracy (%95 C.I.) of FNA biopsy for primary mediastinal neoplasms, secondary neoplasms and nonneoplastic lesions were found to be 93.3 (83.8–98.2)%, 100 (95.1–100)%, 93.3 (83.8–98.2)%, respectively.Conclusion Image guided percutaneous FNA biopsy is a safe and highly accurate diagnostic method for equivocal mediastinal masses.  相似文献   
110.
The purpose of this study is to present the results of the arthroscopic treatment of lateral epicondylitis. Twenty patients with lateral epicondylitis (mean age 42 years) were treated arthroscopically. The average duration of symptoms prior to surgery was 14 months. The arthroscopic joint inspection showed an intact capsule in seven patients (type-I lesion), in eight patients a linear capsule tear (type-II lesion) and in six patients a complete rupture of the capsule (type-III lesion). An associated intraarticular pathology was documented in eight patients. Within an average follow-up period of 1.8 years, local pain and function were documented and analyzed. Subjective pain at rest was reduced from 5.0 to 0.5 points, pain at daily living activities from 6.0 to 1.0 points and pain at athletic activities from 7.3 to 1.2 points in the VAS score. Function increased from 5.2 to an average value of 10.9 (max. 12 points). Patients returned back to work after 3.2 weeks. In conclusion, the arthroscopic release in patients with radial epicondylitis is a reproducible method with a marked postoperative increase in function within a short rehabilitation period.  相似文献   
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